fix: use pkg-config wrapper script instead of exporting PKG_CONFIG_PATH (avoids OF Makefile bug)

scripts/build.sh

@@ -181,11 +181,29 @@ fi
 
 cd "$ADDON_DIR/example_basic"
 GLOBAL_FLAGS="-Wno-error -Wno-reorder -Wno-sign-compare -Wno-delete-non-virtual-dtor -std=c++11 -O0 -fno-tree-vrp"
-# Point pkg-config to the aarch64 .pc files installed by the :arm64 packages
+
-export PKG_CONFIG_PATH="/usr/lib/aarch64-linux-gnu/pkgconfig:/usr/share/pkgconfig"
+# The OF Makefile has a bug: it calls `export $(PKG_CONFIG_PATH)` which passes the
-export PKG_CONFIG_LIBDIR="/usr/lib/aarch64-linux-gnu/pkgconfig:/usr/share/pkgconfig"
+# VALUE as a variable name under /bin/sh, causing "bad variable name" errors.
+# Workaround: don't set PKG_CONFIG_PATH in the environment at all.
+# Instead, create a thin wrapper script and pass it via OF's PKG_CONFIG make variable.
+PKGCFG_WRAPPER="/usr/local/bin/aarch64-pkg-config"
+cat > "$PKGCFG_WRAPPER" << 'PKGCFG_EOF'
+#!/bin/sh
+exec env \
+  PKG_CONFIG_PATH=/usr/lib/aarch64-linux-gnu/pkgconfig:/usr/share/pkgconfig \
+  PKG_CONFIG_LIBDIR=/usr/lib/aarch64-linux-gnu/pkgconfig:/usr/share/pkgconfig \
+  PKG_CONFIG_SYSROOT_DIR="" \
+  pkg-config "$@"
+PKGCFG_EOF
+chmod +x "$PKGCFG_WRAPPER"
+
+# Ensure PKG_CONFIG_PATH is not set in our environment (avoid the OF Makefile bug)
+unset PKG_CONFIG_PATH
+unset PKG_CONFIG_LIBDIR
+
 make clean 2>/dev/null || true
 make -j1 \
+  PKG_CONFIG="$PKGCFG_WRAPPER" \
   PLATFORM_ARCH=aarch64 \
   CROSS_COMPILING=1 \
   CC=aarch64-linux-gnu-gcc \